International DT MaxxForce Engine Low Power Tip

imported_John Whelan - September 28, 2015
MaxxForce DT Preventive Maintenance Low Power No Codes

This condition no power no codes is a common problem with diesel engines. So the first steps are simple like checking for obvious problems with the fuel injection and air intake system. The fuel filters and air filter are exactly where you want to start. I'm not trying to be smart here everyone in the trade who has some years under their belt will say “duh” you think?

Totally acceptable but for the few or more who don't check the simple things first this is for you. I'm saying this with a smile on my face by the way. Recently I talked to one of the dealer techs and he told me about the soot build up that actually slows down turbo rpms causing a loss of power. The main cause of this is a plugged up engine crankcase breather.

A service kit is available for the MaxxForce DT diesel engines that allows mechanics to disassemble the low pressure and high pressure turbocharger on the compressor side (intake) and remove the soot buildup. One tip I caught wind of was to check the crankcase breather with a stethoscope you can hear the internal breather wheel turning after the engine is shut down. This indicates the breather is still operational.

The kit has o-rings and clamps along with a carb cleaner spray that helps to loosen the soot off of the compressor wheel. I recommend Kleen Flo which works great with a soft brush. Even an old tooth brush works. Once you see how bad the soot and carbon build up is you'll understand clearly why there is a loss of power. This build up actually slows down the turbocharger and causes sluggish launches and poor performance under load with no codes showing up.

The Photo below shows the soot build up before cleaning. Any kind of carb cleaner spray works well. Click on the photo to enlarge it to get a better idea how much of the soot collects on the compressor wheel.


The turbo piping has to be removed from the compressor side along with the connections to the engine crankcase breather. Once the 2 housing are removed the clean up can be done easily. All of the piping has to be cleaned up as well. Since the cause of this was excessive oil being drawn into the intake system the engine crankcase breather has to be replaced.

Once it fills up the wheel that separates the oil and vapour can't do it's job. Now that this has happened to us we will be replacing the breather once a year. It's also recommended to check the air filter for any restriction. This of course will cause more of a low pressure area in the intake system. If you're working on the MaxxForce DT you must have the servicemaxx software. After this operation is completed a MAF recalibration is needed.

Instructions come with the turbo service kit so don't delay. If you're experiencing these low power symptoms and you know that the engine crankcase breather has not been serviced for a long time this procedure may help you out. We've had a few buses in our fleet get this treatment and there was a remarkable difference afterwards.
Diesel Engine
International diesel engine
DT MaxxForce